Passengers began leaving the hantavirus-stricken cruise ship MV Hondius on Sunday after the vessel arrived off Tenerife in Spain’s Canary Islands, as authorities launched an evacuation operation.

Officials said none of the more than 140 people still aboard are currently showing symptoms of hantavirus, according to the Associated Press.

Spanish authorities, the World Health Organization and cruise operator Oceanwide Expeditions said the evacuation is being carried out cautiously, with health screenings conducted before passengers are allowed to leave the vessel.

The outbreak has been linked to three deaths. So far, five passengers who previously departed the ship tested positive for hantavirus, which is a rare infection that can lead to severe and potentially life-threatening illness.

Officials said each passenger disembarking in Tenerife will undergo additional symptom checks and will only be permitted to leave once evacuation flights are prepared to transport them to their final destinations. Authorities hope to complete the evacuation operation between Sunday and Monday.

The passengers and crew aboard the MV Hondius reportedly represent more than 20 nationalities.